1. Field of the Invention
This invention relates to a structure of speakers.
The present application claims priority from Japanese Application No. 2004-85061, the disclosure of which is incorporated herein by reference.
2. Description of the Related Art
FIG. 1 is a sectional view illustrating the structure of a conventional speaker.
In FIG. 1, a damper 2 is interposed between a frame 1 and a voice coil bobbin 4. The voice coil bobbin 4 is coupled to a diaphragm 3 and supported by the damper 2 in such a manner as to permit it to vibrate in the axis direction. A portion of the voice coil bobbin 4 around which a voice coil 5 is wound is inserted into a magnetic gap between a yoke 8 and a plate 6 and magnet 7 which form a magnetic circuit. The magnetic circuit gives rise to the vibrations of the voice coil bobbin 4 and the diaphragm 3 in the axis direction.
The conventional speaker has the yoke 8 coupled to a part of the bottom portion of the frame 1 in order to support the magnetic circuit.
However, the speaker of the structure as described above may possibly produce dissonance because when the speaker is driven, the magnetic circuit reacts to the vibrations of the voice coil bobbin 4 and the diaphragm 3, whereupon the vibration is transmitted from the yoke 8 to the frame 1, and then from the frame 1 to portion of the speaker-mounted structure.